MEXICAN DRUG CARTELS' NEWEST WEAPON: COLD WAR-ERA GRENADES MADE IN U.S.

MEXICO CITY -- Grenades made in the United States and sent to Central
America during the Cold War have resurfaced as terrifying new weapons
in almost weekly attacks by Mexican drug cartels.

Sent a generation ago to battle communist revolutionaries in the
jungles of Central America, U.S. grenades are being diverted from
dusty old armories and sold to criminal mafias, who are using them to
destabilize the Mexican government and terrorize civilians, according
to U.S. and Mexican law enforcement officials.

The redeployment of U.S.-made grenades by Mexican drug lords
underscores the increasingly intertwined nature of the conflict, as
President Felipe Calderon sends his soldiers out to confront gangs
armed with a deadly combination of brand-new military-style assault
rifles purchased in the United States and munitions left over from the
Cold War.

Grenades have killed a relatively small number of the 25,000 people
who have died since Calderon launched his U.S.-backed offensive
against the cartels. But the grenades pack a far greater psychological
punch than the ubiquitous AK-47s and AR-15 rifles -- they can
overwhelm and intimidate outgunned soldiers and police while reminding
ordinary Mexicans that the country is literally at war.

There have been more than 72 grenade attacks in Mexico in the last
year, including spectacular assaults on police convoys and public
officials. Mexican forces have seized more than 5,800 live grenades
since 2007, a small fraction of a vast armory maintained by the drug
cartels, officials said.

According to the Mexican attorney general's office, there have been
101 grenade attacks against government buildings in the past 3 1/2
years, information now made public for the first time.

To fight back, U.S. experts in grenades and other explosives are now
working side by side with Mexican counterparts. On Thursday,
assailants detonated a car bomb in downtown Ciudad Juarez, killing two
federal police officers and an emergency medical technician and
wounding seven.

The majority of grenades have been traced back to El Salvador,
Guatemala, Honduras and Nicaragua, according to investigations by
agents at the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives
and their Mexican counterparts. ATF has also found that almost 90
percent of the grenades confiscated and traced in Mexico are more than
20 years old.

The administrations of Ronald Reagan and George H.W. Bush sent 300,000
hand grenades to friendly regimes in Central America to fight leftist
insurgents in the civil wars of the 1980s and early 1990s, according
to declassified military data obtained through the Freedom of
Information Act by the Federation of American Scientists.

Not all grenades found in Mexico are American-made. Many are of Asian
or Soviet and Eastern European manufacture, ATF officials said,
probably given to leftist insurgents by Cuba and Nicaragua's
Sandinistas.

One of the most common hand grenades found in Mexico is the M67, the
workhorse explosive manufactured in the United States for American
soldiers and for sale or transfer to foreign militaries. Some 266,000
M67 grenades went to El Salvador alone between 1980 and 1993, during
the civil war there.

Now selling for $100 to $500 apiece on the black market, grenades have
exploded in practically every region of Mexico in recent years.

In the past year, assailants have rolled grenades into brothels in the
border city of Reynosa. They have hurled one at the U.S. consulate in
nearby Nuevo Laredo. They have launched them at a military barracks in
Tampico and at a television station in Nayarit state.

In the state of Durango, 10 students, most teenagers but some as young
as 8, were ripped apart on their way to receive government
scholarships in March when attacked with grenades at a cartel
checkpoint. The blasts tore a gaping hole in the side of their pickup,
peeling back the door panels as if it were a soda can.

"They are a way to spread fear and terror," said Paulino Jimenez
Hidalgo, a retired Mexican army general. "And they're a way to gain
the upper hand over the authorities."

Grenade attacks began in 2007 in response to the expanded role of the
military in anti-narcotics enforcement and the rise of the Zetas, the
fearsome cartel founded by former special-forces soldiers, according
to Martin Barron Cruz, an expert in arms and security at Mexico's
National Institute of Criminal Sciences, a government agency.

"It's an arms race," Barron said.

Demand for military hardware is soaring, he said, citing recent
seizures of .50-caliber rifles, mortars and anti-personnel mines.

The criminal organizations are demonstrating a growing tactical
knowledge about how to use grenades in close-quarters combat.

"They're a good way to cover your retreat or to initiate an attack,"
said Anna Gilmour, a drug-war expert at IHS Jane's, a global security
consulting firm. "You can use them as a means of spreading confusion."

As one senior U.S. law enforcement official in Mexico put it, grenades
are "a lazy man's killing weapon" because they don't require good aim.

"You don't have to be able to hit a bull's-eye. You just roll it out,"
he said, speaking on the condition of anonymity because of security
protocols.

Frequently, grenades are left unexploded at attack scenes. U.S.
officials attribute this to operator error rather than the age of the
munitions, since grenades can last for decades if stored properly.
While some seized grenades are covered in rust or dirt, others are in
mint condition, suggesting they may have been removed recently from
military stores.

ATF and its Mexican counterparts consider information about the source
country and specific make of grenades classified. Federal police in
Mexico are now offering $200 -- about six weeks' pay at minimum wage
in Mexico -- as a reward for every grenade turned over to
authorities.

U.S. investigators and independent experts suspect that few military
grenades have entered Mexico directly across the northern border from
the United States.

"There might be a few thefts from U.S. military bases, but there has
been little evidence that grenades in Mexico are being smuggled from
the United States," said Colby Goodman, an arms trafficking expert at
the Woodrow Wilson International Center for Scholars.

Interviews with military, police and U.S. law enforcement agents in
Central America suggest authorities are increasingly concerned about
preventing thefts from grenade stockpiles but are virtually powerless
to prevent the spread of weapons that are already loose.

"Almost all of the attacks we've seen have been with M67s," said
Howard Cotto, a chief investigator with El Salvador's National Civil
Police. "There are so many of them floating around here."

Salvadoran police have seized 390 M67s since 2005.

Black-market grenades are so easy to obtain in El Salvador that street
gangs routinely use them as tools of extortion, to menace business
owners and bus drivers. Concern that grenades could leak out of army
garrisons prompted the Salvadoran military to consolidate its abundant
supply in two high-security facilities last year, the Salvadoran
defense minister, Gen. David Munguia Payes, said in an interview. The
U.S. government is planning to send a threat-assessment team to the
country to help secure its arsenals.

"Since 2009 we haven't registered any missing grenades," Munguia Payes
said. "But we know that there are grenades out there on the black market."

In Guatemala, aging American-, Israeli- and Asian-made grenades have
been seeping out of the country's Mariscal Zavala armory for years,
according to military officials and security experts.

The military official who oversees the arsenals, Col. Luis Francisco
Juarez, said safeguards are now in place to ensure that no weapons are
illegally removed. But Guatemalan court records show that when his
predecessor, Col. Carlos Toledo, reported to his superiors last year
that 500 weapons were missing, he was stripped of his command and
subjected to death threats.

Just two months after Toledo reported the missing weapons, arms
diverted from the Guatemalan military turned up at a bloody scene
where five police officers were killed while allegedly trying to steal
370 kilos of cocaine from a cartel safe house. A huge arms cache was
uncovered at the site, including more than 550 40mm projectile
grenades, many of which had lot numbers matching those in the
Guatemalan armory and which appeared to be manufactured in the United
States, according to military and legal sources.

In another large seizure, 500 grenades were recovered in March 2009 at
a site in northern Guatemala that authorities described as a training
camp run by the Mexican Zeta drug organization.

An investigation by Guatemala's El Periodico newspaper found that as
many as 27,000 military weapons, including an unknown number of
grenades, may have been illegally sold or stolen in recent years.

Miroff reported from El Salvador and Guatemala.